FoxOne

I'm puzzled over very similar specs of Powered Up L and XL motors, according to Philo's research. I believe I'm not the only one though )). It looks like a good move to invest only in L motors, since they are lighter, smaller and just as powerful. But what's the catch? Are there any insights on the subject? Any additional field test results? Looking forward, thanks!

Happy to share, will follow your project! One more thing in favor of AWD: Without proper castor, it's a challenge to drive accelerating RWD car in a straight line. No such problem in AWD mode, and acceleration rate is better. Another crazy setup would be FWD with a handbrake. Not sure if it's practical with standard motors, too much weight (extra motor to power handbrake).

So I've been inspired by Gears of Doctor / RM8's drifting performance, too )). As a result, I've built a simple testbed for a drift car concept. It's capable of decent performance on a hardwood floor, doing both donuts and controllable power slides. It's powered by 2 * PU XL motors, plus 1 * PU L for steering, and uses a standard Control+ hub. I skipped suspension, Ackermann and castor, for the sake of simplicity and building speed. There's ain't no bodywork as well, since it's a testbed. U-joints for the steered axle, 4WD drive, forward open diff, rear is welded. The following is a sort of a long read -- please kindly let me know if it's considered the offtopic. ------------ I've done some tests while experimenting with it, happy to share / discuss. Goes without saying it applies to Lego plastic cars, and not everything can be projected to real life scenarios. My findings are: Most important factors for drift performance are Power, Steering geometry and Wheels traction Out of these three, Traction affects performance the most (in Lego case, of course). Given wheels are slippery enough you can brake traction with almost any reasonable power / geometry, but doing controllable stunts requires fiddling with different types of wheels. I ended up with plastic rims from 42099's wheels on the rear axle, and some strange orange plastic wheels form 10 years old Mars Rover (Mars Invasion, Creator series, smth like that). I've also tried regular rubbery wheels w and w/o taping them, but this (plastic ones) particular configuration has proved the best. Talking of Power, it's a combination of 3 factors: model weight, power plant power and it's distribution between axles. -- it's easier to brake traction with lightweight model -- trying to get something overpowered enough with standard motors / power (i.e. w/o BuWizz and buggy motors) isn't simple, to say the least -- regarding drive type, tried and true configuration is 4WD with welded rear diff I've compared different configurations myself: -- RWD, welded rear diff -- easy to break traction, but it's only donuts and sharp uncontrollable U-turns; weak acceleration -- 4WD, welded rear diff -- donuts and U-turns are still possible, but not so sharp; nice controllable power slides; healthy acceleration rate -- 4WD; both diffs welded -- doesn't turn at all -- 4WD or RWD; both diffs open -- very hard to break traction Geometry boils down to wheel base and max steering angle: -- it was a lot easier to drift with the short wheel base, but it's harder to control the skid -- larger max steering angle has a strong impact on breaking traction And 2 more finding re geometry: -- rate of steer is of importance, too -- the faster, the better -- I've tried to drift even with articulated steering -- in short, it's next to impossible No effect / haven't tried yet: -- weight distribution between forward and rear: I moved the hub along the longitudal axis, but effect was negligible; maybe wheel base was too short to notice the difference -- there's a recipe to drive rear axle with higher RPMs than forward; kinda tried that, using bigger wheels at the rear, to no avail -- I was limited with the choice of wheels, but small wheels (with appropriate transmission adjusting) should be better, due to faster acceleration Sort of serendipity: If a rear side of your forward wheel touches the chassis and stops at the extreme steering angle, it promotes very sharp and clean donut: braked wheel becomes the pivot, while the forward differential moves all the torque to the opposite wheel, promoting the spin even further Bonus track: First prototype was built on EV3 platform, with 2 EV3 large motors for driving. Oh man..those beasts do pack a punch, but ain't have no RPMs, was a quest to gear it up enough; that and sheer weight / size of EV3 made it ineffective, though I made it drift a little with taped wheels

Looks awesome, thanks! Have you thought about connecting RC-servos to PU hub also? Trying to decide if it worth the effort, or just let go of standard controller altogether.

Oh, that ridiculously overpowered 42065 had triggered me, too)). Bet it was RacingBrick's version, right? I was able to pull it off with one BuWizz and 2 XL's. Very lightweight vehicle, basically bare chasis without any bodywork. In this configuration she's able to drift a little on a hardwood floor, in high gear. (I have also integrated some simple 2-speed gearbox, to negotiate some 50 degrees slopes as well).

If you decide to proceed with EV3 you will also need EV3 motors. The thing is they're in class of their own -- not compatible with other Technic controllers (except NXT). Moreover, they have very specific use case in robotics, and using them in regular Technic vehicles takes some creativity. So if you're thinking of reusing parts of this installation later, maybe it's better to use something from new Powered Up ecosystem. That also includes Robots Inventor / Spike Prime.

Could be wheels from RI / Spike Prime also.

@Templar Do you consider using smartphone? There are some apps available, able to control your hub (battery box) without any coding involved. That could be done with our without adding gamepad controller like Sony Dualshock.

Gents, I'd like to highlight another angle on this sensitive topic. Being from software industry myself, my personal opinion leans towards respecting author's and owner's decision, either to share instructions and partslist or not. But, frankly speaking, owning the bricks and seeing this gorgeous model, with clear restriction to build it, is rather confusing, to say the least. That makes me wonder whether additional copyright-related means could be applied. Just for the sake of discussion, maybe something like "for personal / non-commercial use only" or "expiration period of legal protection"? Another approach could be to sell legal instructions by vendor itself, but it's clearly their own business decision. I'm also not a lawyer (c), but look -- Torsen differential is patented; is it ok to build it with bricks?

I believe embedded servo mode is the main reason. As a bonus, PU XL's are pure joy to mount, compared to cylinder-like PF 's.